Spark-plug



. H. L. FLOOD.

SPARK PLUG. y APPLICATION FILED MAR. 21, 19l9. RENEWED AUG. 30, 92.

Lfr. Patented Dec. 13, 1921.

l Zi/ML@ A TTORNE Y.

fil

'cleanedT notwithstanding 'soiree srAres Liemers.

fpeeeeten or Letters Betentl Patented Dec. 13, 1921.

.ppleation le Marel! 21, l, Serial. l'o. fl. Renewed august 3l), 1921. Serial No. 497,(l47. j

To (2,313 207mm 5' 'ni/.Ly @officer/n Be it linotrn that i, Preis r fieri Frooo, o

Ponce lli'ty, in the county o ond State ofi ldeliome, lieve inventednew end'userul improvements in Spark-Plugs, oi" Wli tne :following is' e. specification. lily present invention pertains to sourir plugs and consists in the peculiar. s srl inlog possessed of certain practical, features oiI advantage chief among Wliicii is tlia't the porcelain insulation may be removed to b the is properly classed e one-piece plug, as herein after described and definitely eleroed.

in tire eceompenying drei-rings hereby mede eport hereof z Figure l is a side elevation of the speri: plug constituting tile reterred embodiment of my invention.

F 2 is en enlarged diemetricelv section ci tbe seme. I

Fig. 55 is on enlarged side elevation oi' 'the inner end or the plug.

Il is e transversesection teken in the plone indicated by the line l--- of E l.

Similar numerels of reference designee corresponding ports in ell of die views of the dre win gs inong other elements my novel plug eoinprises e. shell i, prefereb of steel. The seid shell is exterior-ly three-ded et P9 and interiorly vthreaded ei; $3j and is provided with the usuel angular portion for the :implication or' e wrench or the like.

Lslitteciied to tbe inner end of tbe shell l is u lieei'y cest or wroughtiron bridge 5 which possesses a iiigiier melting point then other metals. and hence is not liable to be come red liot and. give rise to pre-ignition or to be destroyed by the intense liest to which it is subjected. Tile bridge 5 is ticlied to the shell by providing opposite gee-s 6 in the inner end of the sliell, dispos: ing *lie ends of the bridge in seid gap, end

then burringr the bridge inplecc with s set' punch. As indicated by 7, the bridge is coated with rire-clay cement suoli es 1s used on ges mantle supporting wires, tbe seid coating having e tendency to preclude red beating of the bridge. tteobed to the bridge 5 for grounding purposes is en ailoy sparking' point 8.

The const-motion of my plug renders' it,

unnecessary to remore the siiell i from the motor when it is necessary to aleen the por celziin insoiation, es the points require no Aedf'ustnent and there :1re no copper gaskets likely to cause troobie.

My novel plu also commises e bushing 9, preferably or steel. that threaded at 1U and is of angular form at ,11, and is provided in its outer end with e cup l2. The interior of the said bushing 9 1s tapered outwardly as indicated by 1.3.

Bieposed in the taper 13 of the bushing 9 and depending or estending inwardly from seid bushing is alie insulating body 14, said body being preferably of porcelain. ln assembling the insulating' body 14 and the b [slung S,

tlie outwardly 'tapered portion t insuletingbody is Wrapped with esbestos yarn l5, 'and the tapered interior 13 or the bushing' isl iilied with expansion and Water end heetioroof cement 16. The -inner end or' the bushing 9 is burred ever the inseleting body 14. at the lower end of the 'tapered portion thereof, is indicated by l?.

i 'ely tbe disposition of the outwardly tapered portion of the insulating body 14; in 'the correspondingly tapered interior of the bushing' will result in. the insulating body being tightened in thebushing when the plug is subjected to the action of an explosion. Moreover the asbestos yerni 15 and the cement 1&6 will form a bushing endwill taire core or" expansion and contraction, with the result tiret tl're iiability of breakage will be reduced to e minimum. Again breakage is.; practically.eliminated by the fact that the removal of eil other parte of the plug from the sliell i and the reeinsert'ion of said parte ere effected by screwing the metallic bushing il out of and into tbe shell, no art other than 'the bushing' 9,-connecting Wit the shell il. lt will further be noted in this conneceion that the insulating body 14 islpermanent-ly aHiXed in the bushing 9, and that when che bushing 9 is turned out of the shell 1, the insulatingi body may be readily .and thoroughly cieened. l

Disposed in tile cup 12 at the outer end of. the bushing Q is en esbestoswasher 18 to which is opposed the inner end 'of the insuleting oep 19, preferably of porcelain. The said cap i9 is preferably provided With cement et its inner end, and 'is slipped ovjer, the outwardly extending tubular ortion20 of 'toe insnieting body le, and has its inner opposed. to tile seid washer 18. The

con 3.9 adds materially to'the,insulationony .is exteriorly ness or oil or other substance from causing eXterir short ciro'uiting. Manifestly thelargesurfaoe'ot the 'cap 19 contributes to- Ward these ends. l The tubular insulating portion 20 rejects outwardly Vbeyond the metallic bus ing 9. The said tubular portion 2O is provided with a diametricalaperture 2l that intersects the longitudinal biere 22 and a'ords 'a peek-hole opposite the `intensifying gap. Extending through the longitudinal center of the insu? lating body 14 is the conducting Wire 23,.the inne-r end of which is exposed at the inner end of the body lt, and is opposed to the point 8 of the 'bridge 5. ll/lanifestly this arrangement of the terminal of the Wire 23 and the considerable portion of insulating body la between -said terminal and the shell? l contributes lmaterially to *preventing Wire 27 the nnerendo Whioli is opposed to the outer end of the' conducting Wire23.

` Wire 23 to 4closelthe gap, whereupon the plug Y vthat lacks the lgap The Wire 27 may .belplaced against .the

Will operatelin the saine manner as a plug Again the Wire 27 may be 'moved Withespect to the Wire 23 to 'ad-f ',just the gap.Y The spindle 26 is threaded andy holds the terminal nuts 26a together With= the intensifying nut 2 8. The latter nut is preferably integral with the Wire 27 so that the said wire may be adjusted andl'adjustably lined with respeot to 'the Wire 23. At its inner end the spindle 2 6 is provided With a large and thin head 30 which' is disposed below the top of a brasscap 3l that is burred at 32 into the tubular portion 20. Mani'- estly by turning the nut28 the gap may be increased or diminished in .size or ma -be entirely eliminated in the'discretion o the user.

Having described my invention, what I claim and .desire to secure by Letters-Patent, is: 2.11. In a spark plug, the oombination'of an inteiorly and exteriorly threaded sliellts oflre resulting from a leaky- Modera' y bushing threaded into and 'removable from said shell, .an insulating body fixed in and extending inwardlyfrom the bushing andliaving a tubular portion extending outwardly from the bushing, an insulating cap disposed over saidI tubular portion, a spark point at the inner end of the shell, awire ex'- tending through the insulating body and havingits inner end 'opposed to said point, a threaded spindledisposed in the' tubular ing Wire extending through said insulatingbody and having its outer end disposed opposite the aperture in the tubular. portion, an insulating cap arranged over said tubular portionand having an aperture in registra-v tion Withsaid diametrical aperture, a spindle containing a Wire opposed to the outer end of the first-named Wire, and aI--ftdjustf ing cap engaging` the spindle and carrying the secondi-named Wire;

3. ln a 'spark plug, the combination of an which is aldiametrical aperture, a oonducting ,vireleiitending through said lnsulatlng `portion of the insulating body and th cap. l ,and containing a Wire opposed to the outer end of the first-named Wire, anda cap en` vinsulating body having a tubular portion in body andv having its outer end disposed oppo- 1 site the.E aperture in the tubular portion, an

'insulating cap larranged over said tubular portion and having an-'aperture 1n registration with saiddiametrical aperture, a spindle ,containing a wire opposed to the outer l end of thelirstenamed Wire, an adjusting cap Iengaging' thespindle and carrying the seoond-named wire,- and a mica guard Wall carried in theinsulating cap and Covering the aperture therein.

4. In a spark plug, the combination of an insulating body having a tubular portion,a metallic cap arranged over said tubular portion and having its side wall -burred into the same, a tubularspindle having a head vdisposed under the `cap and also having an exterior threads4 threaded oap'on said spinldle, and awire carried by the cap and mov able' through the. tubular portion and also' through the'spindle.

' In testimony whereof I affix my signature.

HENRY LEE FLoon i 

